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Efficacy of Do-It-Yourself Whitening as Compared to Conventional Tooth Whitening Modalities: An In Vitro Study


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Aim: To evaluate the efficacy of do-it-yourself (DIY) whitening as compared to conventional tooth whitening modalities using different shade assessment tools. Methods and materials: Extracted human molars (120) were randomly distributed to six groups (n=20). Whitening was performed according to manufacturer's directions for over-the-counter, dentist-dispensed for home use, and in-office whitening. DIY whitening consisted of a strawberry and baking soda mix. Additionally, negative and positive controls were used. Two evaluators used the Vita Classical (VC) and Vita Bleachedguide 3D-Master with interpolated numbers (BGi) for visual assessment at baseline and one-week, one-month, and three-month postwhitening. Instrumental measurements were performed with a spectrophotometer. Kruskal-Wallis procedure was used to assess color changes among groups and intraclass correlation (ICC) to evaluate agreement between evaluators. Results: DIY exhibited lower color change (ΔSGUVC, ΔSGUBGi, ΔE*, where SGU = shade guide unit and E = overall color change) compared to other whitening groups at all time points (p<0.05). ICC demonstrated very good agreement between evaluators with VC and BGi at each time point. Both shade guides were related with each other and strongly related to instrumental measurements (p<0.05). Conclusions: DIY whitening was the least effective whitening modality. Both VC and BGi are related with each other and have good correlation with instrumental measurements.
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Efficacy of Do-It-Yourself Whitening
as Compared to Conventional Tooth
Whitening Modalities: An In Vitro
SR Kwon M Meharry U Oyoyo
Clinical Relevance
Professionally applied in-office whitening, professionally dispensed patient-applied home
whitening, and the use of an over-the-counter product are effective in changing tooth color
toward a lighter shade, whereas do-it-yourself whitening is not an effective tooth whitening
Aim: To evaluate the efficacy of do-it-yourself
(DIY) whitening as compared to conventional
tooth whitening modalities using different
shade assessment tools.
Methods and Materials: Extracted human mo-
lars (120) were randomly distributed to six
groups (n=20). Whitening was performed ac-
cording to manufacturer’s directions for over-
the-counter, dentist-dispensed for home use,
and in-office whitening. DIY whitening con-
sisted of a strawberry and baking soda mix.
Additionally, negative and positive controls
were used. Two evaluators used the Vita Clas-
sical (VC) and Vita Bleachedguide 3D-Master
with interpolated numbers (BGi) for visual
assessment at baseline and one-week, one-
month, and three-month postwhitening. In-
strumental measurements were performed
with a spectrophotometer. Kruskal-Wallis pro-
cedure was used to assess color changes among
groups and intraclass correlation (ICC) to
evaluate agreement between evaluators.
Results: DIY exhibited lower color change
,DE*, where SGU =shade
guide unit and E =overall color change)
compared to other whitening groups at all
time points (p,0.05). ICC demonstrated very
*So Ran Kwon, DDS, MS, PhD, MS, associate professor,
Department of Operative Dentistry, University of Iowa
College of Dentistry, Iowa City, IA, USA
Michael Meharry, DDS, MS, associate professor, Midwestern
University Dental Institute, Glendale AZ, USA
Udochukwu Oyoyo, MPH, assistant professor, Dental Educa-
tion Services, Loma Linda University School of Dentistry,
Loma Linda CA, USA
Yiming Li, DDS, MSD, PhD, professor and director, Center for
Dental Research, Loma Linda University School of Dentistry,
Loma Linda CA, USA
*Corresponding author: Department of Operative Dentist-
ry, University of Iowa College of Dentistry, 801 Newton
Rd, #45, S235 DSB, Iowa City, IA 52242-1001, USA; e-mail:
DOI: 10.2341/13-333-LR
Operative Dentistry, 2015, 40-1, 000-000
good agreement between evaluators with VC
and BGi at each time point. Both shade guides
were related with each other and strongly
related to instrumental measurements
Conclusions: DIY whitening was the least ef-
fective whitening modality. Both VC and BGi
are related with each other and have good
correlation with instrumental measurements.
Demand for tooth whitening has been building and
growing for more than a decade as people envision
and desire a ‘‘Hollywood smile.’’ Tooth whitening
now represents the most common elective dental
and has proven to be safe and effective
when supervised by a dentist.
More than 1 million
Americans whiten their teeth annually, driving
nearly $600 million in revenues for dental offices.
The high demand is also reflected by the wide range
of whitening modalities available: professionally
applied in-office whitening; professionally dispensed
patient-applied home whitening, and over-the-coun-
ter (OTC) products.
The penchant to do it yourself has swept through
myriad websites promoting the use of at-home
whitening remedies,
including rubbing crushed
strawberries or apples on the teeth. Thus, a new
category has emerged that can be described as do-it-
yourself (DIY) whitening using natural ingredients.
The advocated use of fruits such as strawberries and
apples is based solely on anecdotal evidence with the
rationale that they contain malic acid. Considering
the current evidence of the erosion potential of fruit-
containing beverages and smoothies
and contro-
versies on the safety of DIY methods,
cautions for their use in tooth whitening is para-
Tooth whitening efficacy has been evaluated
visually with clinically accepted shade guides and
instrumentally with electronic color measuring
devices. The Vita Classical (VC; Vita Zahnfabrik,
Bad Sa
¨ckingen, Germany) developed in 1956 is one
of the most commonly used shade guides. However,
its use in monitoring tooth whitening has been
disputed due to a lack of logical order, uniform color
distribution, and light shade tabs, thus limiting the
design of whitening studies.
The Vita Bleached-
guide 3D-Master (BG; Vita Zahnfabrik) was intro-
duced in 2007 to increase the reliability and
validity of visual color assessments by including
more whitening shade tabs, uniform distribution
between the tabs, and a visually perceivable light
to dark value order.
The BG tabs are now
available with new markings, with each tab
marked with odd numbers from 1 to 29 and with
‘‘interpolated’’ even numbers in between. The main
advantage of the interpolated BG (BGi) that has
been reported is that the distribution of the tabs
better corresponds to the American Dental Associ-
ation (ADA) equation that 1 ccu =1SGU=1DE*
(ccu =color change unit; SGU shade guide unit;
DE* =overall color change).
With heightened consumer interest in whiter
teeth, it is the responsibility of the dental profession
to educate the patient and the public about the
efficacy and adverse effects of different tooth
whitening modalities, suggest or provide appropriate
whitening options based on patient’s needs and
preference, and establish reliable and valid monitor-
ing tools for the whitening process. According to the
current literature, there seems to be a lack in
knowledge of comparing whitening efficacy of all
four whitening modalities. There is also a lack of
information on the correlation of the newly intro-
duced interpolated shade guide with conventional
shade guides.
The purpose of this study is to compare the efficacy
of DIY whitening as compared to conventional
whitening modalities with respect to tooth color
change. Tooth color change was monitored with
three different shade evaluation methods: visual
assessment using VC and Interpolated BGi and
spectrophotometric color assessment with the Vita
Easyshade Compact (ES; Vita Zahnfabrik).
The null hypotheses to be tested were the
following. First, there will be no difference in tooth
color change among the four different whitening
modalities. Second, there will be no differences in
agreement between the two evaluators using VC and
BGi. Third, there will be no correlation between
visual and instrumental color measurements.
Sample Selection and Preparation
Extracted sound human third molars without iden-
tifiers (120) were collected and stored in 0.2% sodium
azide solution at 48C. Teeth were cleaned of gross
debris and placed in artificial saliva for 24 hours at
378C prior to initiating the experiment. Artificial
saliva was prepared and replaced daily according to
the modified Fusayama solution as described in
ANSI/ADA Specification 41.
2Operative Dentistry
Experimental Groups
Specimens were randomly distributed into six
groups of 20 specimens each and mounted on acrylic
molds to expose the crown portion for the different
whitening treatments. The active ingredient, pH,
and application regimen by group are summarized in
Table 1. The treatment regimen for each group
followed manufacturers’ instructions or recommen-
dations for typical use. DIY represented a method
using a puree of strawberry (15 g) mixed with baking
soda (2.5 g; Arm & Hammer Baking Soda, Church &
Dwight Co, Inc, Princeton, NJ, USA) for five minutes
followed by brushing with a soft toothbrush (Colgate
Oral Pharmaceuticals, Inc, New York, NY, USA) for
30 seconds. The procedure was repeated two more
times at five-day intervals. Group OTC received
daily applications of whitening strips for two hours
(Crest 3D Intensive, Crest Pro Health, Procter &
Gamble, Cincinnati, OH, USA) for seven days. Group
HW was treated with a 10% carbamide peroxide gel
(Opalescence PF, Ultradent Products Inc, South
Jordan, UT, USA) placed in a custom fabricated tray
for six hours for 14 days (0.12 ml/tooth). Group OW
represented the professionally applied group treated
with 25% hydrogen peroxide (Philips Zoom White
Speed, Philips Oral Healthcare, Los Angeles, CA,
USA) with three applications for 45 minutes using
light activation. The whitening material was replen-
ished every 15 minutes according to the manufac-
turer’s instructions. The negative (NC) and positive
control (PC) groups were treated according to the
International Organization for Standardization
(ISO) 28399 protocol with grade 3 water and 1.0%
citric acid for 60 minutes at 358C, respectively.
Tooth Color Change Assessment
Two shade guides, the VC and BGi, were used for
visual color assessment (Figures 1 and 2). Measure-
ments were performed under a color-controlled light
box (MM 4e GTI Mini Matcher, GTI Graphic
Technology, Inc, Newburgh, NY, USA) at CIE D
a color temperature of 6500 K, and light intensity of
1200 lux by two evaluators with superior color
matching competency (ISO/TR 28642).
were expressed in difference of shade guide units
(DSGU) for the respective shade guides. Instrumen-
tal color measurements were performed on the
middle third of the buccal surface using a contact-
type intraoral spectrophotometer (ES), Vita Easy-
shade Compact, with the use of a custom-fabricated
clear jig for repeatable measurements (Figure 3).
The overall color change as measured with the
Table 1: Active Ingredient, pH, and Application Regimen by Group
Group Concentration pH Application Regimen
NC: water of grade 3 7.0 One application (60 min), at 358C
DIY: strawberry mix CA 7.2 Three applications (5 min each) at 5-d intervals
OTC: Crest 3D Intensive 9.5% HP 6.0 One daily application (2 h) for 7 d
HW: Opalescence PF 10% CP 7.4 One daily application (6 h) for 14 d
OW: Zoom WhiteSpeed 25% HP 7.2 Three applications (45 min each) at 5-d intervals
PC: citric acid 1.0% CA 3.9 One application (60 min), at 358C
Abbreviations: CA, citric acid; CP, carbamide peroxide; DIY, do-it-yourself; HP, hydrogen peroxide, HW, home whitening; NC, negative control; OTC, over-the-counter;
OW, office whitening; PC, positive control.
Figure 1. Value-oriented Vita Clas-
sical Shade Guide.
Kwon & Others: 3
spectrophotometer was expressed as DE* from the
Commission Internationale de l’Eclairage. The fol-
lowing equation was used:
The color differences were calculated relative to
baseline color parameters (L*
). Measure-
ments were performed with the VC, BGi, and ES at
baseline (T
), one-week postwhitening (T
) and one-
month (T
), and three-month postwhitening (T
Statistical Analysis
Measurements of color change included DSGU
, and DE*. The Kruskal-Wallis procedure
was used to determine significant differences in color
change among the groups. Friedman’s test was used
to evaluate differences in color change across the
different time points. Intraclass correlation (ICC)
was used to assess the agreement between the two
evaluators using the VC and BGi. Correlations
between visual and instrumental measurements
were assessed with Pearson correlations. Tests of
hypotheses were two sided with an alpha level of
0.05. Analysis was conducted with SAS version 9.2
(SAS Institute, Cary, NC, USA).
Visual and instrumental color changes by groups at
Baseline color parameters of the six groups were
not different with the visual and the instrumental
methods (p.0.05). However, color changes among
the groups were significantly different at all time
periods for the visual and instrumental methods
(p,0.05). Post hoc tests (Scheffe) for VC, BGi, and
ES at one week (T2-T1), one month (T3-T1), and
three months (T4-T1) showed that there were
significantly greater color changes in groups OTC,
HW, and OW than in groups NC, DIY, and PC.
(p,0.05). At three months, the greatest overall color
change (DE*) was observed for group OW (p,0.05;
Figure 4). However, visual assessment showed no
difference among OTC, HW, and OW at three-month
Figure 2. Vita Bleachedguide 3D-
Master with interpolated numbers.
Figure 3. Vita Easyshade Compact
and the use of custom-fabricated
clear jigs for repeated measurements.
4Operative Dentistry
evaluation (p.0.05). At three months, NC, DIY, and
PC showed an overall color change of 2.3, 2.4, and
2.53, respectively, which is less than the percepti-
bility threshold of DE 2.6 units.
The levels of ICC demonstrated high agreement
between the two evaluators using both the VC and
the BGi. It is noteworthy that the agreement at
baseline (T1) was significantly lower than the
agreement observed at T2-T4 for both BGi and VC
(Table 3). Assuming linear correlation, the shade
guides were strongly and positively related with
each other. Both shade guides were strongly related
with the instrumental measurements (Table 4).
This is the first study that compared the efficacy of a
DIY whitening regimen as compared to three
conventional whitening modalities. The result of
this study is partially limited by the use of extracted
human teeth, which will inherently differ from vital
teeth in the oral environment. Based on the results,
the first null hypothesis was rejected, as significant
differences in color change were detected among the
four whitening modalities. The second hypothesis
was retained; there was no significant difference in
agreement between the two evaluators when com-
paring both shade guides. The data support the
rejection of the third hypothesis because of strong
correlations between the shade guides and the
instrumental measurements.
Several studies have compared the efficacy of OTC
products, home whitening, and in-office whiten-
According to a clinical study that compared
three different whitening techniques with respect to
the whitening times required to achieve a defined
level of whitening, the cycles required increased
from office whitening to home whitening to OTC
products. That is, one in-office session was compa-
rable to approximately seven days of home whiten-
ing and 16 days of using an OTC product.
clinical study found that home whitening and in-
office whitening were superior to OTC whitening
Table 2: Visual and Instrumental Color Changes (Mean [SD]) by Groups at Three Time Points
Group 1 wk (T2-T1) 1 mt (T3-T1) 3 mt (T4-T1)
NC 0.4(0.8) A0.6 (1.5) AC 3.2 (2.0) A1.3 (1.4) A0.7 (1.8) A2.2 (1.5) AC 1.4 (1.3) A0.1 (1.5) A2.3 (1.0) A
DIY 0.5 (1.1) A1.0 (1.2) A4.0 (1.9) A0.1 (1.8) AC 1.1 (1.4) A4.9 (1.9) AD 0.1 (1.3) A1.0 (2.3) A2.4 (1.4) A
OTC 7.4 (2.4) B11.0 (2.2) B10.0 (2.6) C8.1 (2.0) B11.5 (2.5) B14.6 (2.8) B8.6 (2.3) B12.0 (2.1) B14.0 (3.0) B
HW 7.7 (3.0) B11.6 (2.3) B13.8 (2.4) D7.7 (3.0) B11.4 (2.4) B15.7 (2.8) B7.5 (3.0) B12.0 (2.0) B15.3 (2.4) B
OW 7.7 (1.9) B12.7 (2.0) B17.3 (3.3) E8.0 (2.0) B13.5 (1.9) B18.1 (3.4) B8.0 (2.0) B13.6 (2.1) B17.6 (2.8) C
PC 1.1 (1.2) A1.6 (2.5) AD 5.1 (2.4) A2.0 (1.4) AD 1.7 (1.9) A4.6 (2.1) A1.4 (1.8) A1.4 (2.0) A2.53 (1.0) A
Abbreviations: DIY, do-it-yourself; HW, home whitening; NC, negative control; OTC, over-the-counter; OW; office whitening; PC, positive control.
Within columns, different letters indicate means that are statistically different (p,0.05).
Figure 4. Overall color change (DE*)
by group at different time points.
Kwon & Others: 5
products when followed up for up to three months.
Our study results showed that the whitening efficacy
of Crest Whitestrips, an OTC product, was compa-
rable to professionally dispensed home whitening
and professionally applied in-office whitening for up
to three months postwhitening when evaluated
visually with shade guides. The varying results
compared to previous studies may be explained by
the difference in study design (e.g., in vivo vs in
vitro) and the difference in whitening products
employed. It is important to point out that the
change from original Whitestrips using a polymer-
based hydrogel system to the new advanced seal
technology with an improved seal and increased
hydrogen peroxide concentrations may have affected
the study results.
DIY whitening with strawberries as well as the
positive control group using 1.0% citric acid was not
effective in whitening, which showed that color
change is not due to the acid component in fruits.
Agreement between the two evaluators was very
good for both shade guides VC and the BGi. This is
contrary to a study that showed superior perfor-
mance assessment with the Linearguide 3D-Master
compared to the Vita Classical.
This can be partly
explained by the limitation of the lack of lighter
shade tabs in the VC. After specimens were
bleached, the only choice was the B1 tab, resulting
in high agreement between the two evaluators using
the VC. Thus, it is noteworthy to point out that ICC
was higher for BGi than VC at all time points,
although it was not statistically significant.
The results of this study demonstrated a good
correlation between the two shade guides and the
instrumental measurements. This supports the use
of both shade guides as acceptable tooth shade
guides and the use of electronic color measuring
instruments for laboratory assessment of tooth
whitening efficacy, as described in ADA acceptance
guidelines and ISO Standards.
It also suggests
that, whenever possible, both visual and instrumen-
tal methods should be used, as they complement
each other.
Within the limitations of the study, the data
provided important information about the efficacy
of different whitening modalities. This will provide a
resource to recommend and educate the public about
the most effective tooth whitening modality. Future
studies on the adverse effects of different whitening
modalities should be performed to address the effect
on surface roughness, microhardness, and surface
morphology. Thus, any abuse of tooth whitening that
may lead to moderate to severe loss of tooth
structure may be prevented.
DIY whitening with the use of a strawberry
mixture is not an effective tooth whitening modal-
ity when compared to professionally applied in-
office whitening, professionally dispensed patient-
applied home whitening, and an OTC product. Both
shade guides VC and BGi are related with each
other and have good correlation with instrumental
Conflict of Interest
The authors have no proprietary, financial, or other personal
interest of any nature or kind in any product, service, and/or
company that is presented in this article.
(Accepted 26 May 2014)
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Table 3: Agreement Between the Two Evaluators Using
VC and BGi
Time ICC Confidence Interval
Lower Bound Upper Bound
VC Baseline (T1) 0.777 0.674 0.847
1 wk (T2) 0.924 0.889 0.948
1 mo (T3) 0.95 0.868 0.975
3 mo (T4) 0.954 0.93 0.969
BGi Baseline (T1) 0.86 0.645 0.93
1 wk (T2) 0.966 0.946 0.977
1 mo (T3) 0.984 0.975 0.989
3 mo (T4) 0.982 0.973 0.988
Abbreviation: ICC, intraclass correlation.
Table 4: Correlations Between Visual and Instrumental
Pearson correlation 1 0.896** 0.828**
p-value 0 0
Pearson correlation 0.896** 1 0.890**
p-value 0 0
Pearson correlation 0.828** 0.890** 1
p-value 0 0
** Correlation is significant at the 0.01 level, N=360 in all instances.
6Operative Dentistry
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... As a result, general population began leaning more toward natural products as they are free of chemicals; hence, free of harmful side effects [3], [4]. ...
... In addition, some people choose to whiten their teeth using homemade remedies and traditional methods that are cheap and easily attainable. These methods have swept through the internet gaining popularity [4]. One of which is activated charcoal which has been used for whitening of tooth surface as well as its use in many beauty hacks [5]. ...
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INTRODUCTION: There has been increase in demand to use natural whitening agents nowadays which include activated charcoal. Activated charcoal has gained popularity recently with various claims to its benefits that have not been proven. AIM: The aim of the study was to evaluate the effect of activated charcoal whitening agents and regular whitening tooth paste on enamel surface of first premolars and to compare between the effects of materials used. MATERIALS AND METHODS: Twenty-one mandibular first premolars were used and divided into control group: untreated teeth that were later incorporated into experimental group. Experimental group: Consisting of three subgroups: Subgroup I: treated with Carbon Coco. Subgroup II: treated with Venu activated charcoal. Subgroup III: treated with Crest 3D white. Brushing was done nine s for 30 days then teeth were preserved in artificial saliva. RESULTS: Scanning electron microscopic results showed areas with rodless enamel more observed in Subgroup III than Subgroups I and II. EREs were more numerous on Subgroups I and II than Subgroup III on enamel surface. Partially occluded EREs with precipitates were more observed on Subgroups I and II than Subgroup III. Energy dispersive X-ray analysis results for calcium showed significant increase between all groups with control. The highest value was recorded in Subgroup II followed by Subgroups I and III while control group was the lowest one. Phosphorous showed significant increase between all groups with control. The highest value was recorded in Subgroup I followed by Subgroups III and II while control group was the lowest one. Micro-hardness results of Subgroups I and II showed significant increase compared to control group and no significant difference between control and Subgroup III was detected. CONCLUSION: Powder form activated charcoal is more abrasive than whitening toothpastes. There is no visible difference between pure 100% activated charcoal powder and charcoal powder with additives to it.v
... The 2015 survey data states that more than 1 million Americans are interested in carrying out teeth whitening treatment at a cost of up to 600 million dollars per year [3]. ...
Background: Bleaching treatment is a whitening treatment for discolored teeth to restore their aesthetic function. The bleaching agent that is commonly used is 35% carbamide peroxide. Strawberries contain malic acid which can whiten teeth. Purpose: This study aims to find out acid potential on strawberries as a natural ingredient for teeth whitening. Methods: 48 post-extraction permanent single-rooted teeth that had been coated with clear nail polish were soaked in black coffee for 2 days, then 16 teeth were immersed in a local strawberry extract solution, 16 teeth were immersed in an imported strawberry extract solution and the other 16 teeth were immersed in a 35% carbamide peroxide gel solution and then observed and measured the color of the teeth after immersion at 24 hours and 48 hours. Results: There is potential for local and imported strawberry fruit extract in whitening teeth but the whitening potential when compared to carbamide peroxide is not significant (p>0.05). The whitening potential of imported strawberry juice is higher than that of local strawberry juice based on the average value. Conclusion: Based on research results, local and imported strawberry juice extracts have the potential to whiten discolored teeth.
... This study investigated the whitening effect of discolored resin brackets according to the HP concentration and the number of treatment applications compared with the control group. Methods for measuring the whitening effect included visual observation using shade guides and quantitative evaluation using spectrophotometers, colorimeters, and imaging systems [31][32][33]. Evaluation using shade guides is a common method in dentistry for clinical shade matching and remains a standard method in tooth whitening research [32,34,35]. Therefore, this study used visual observations to record the color change of the resin bracket attached to the tooth surface before and after whitening treatment, to account for situations that are affected by the environment around the bracket. ...
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Objectives. This study aimed to evaluate the whitening effect, shear bond strength (SBS) with the enamel surface, microhardness, and microstructure of discolored resin brackets following whitening treatment with various concentrations of hydrogen peroxide (HP). Materials and methods. Resin brackets were bonded to the enamel surface and discolored with a curry solution. Control (distilled water) and experimental solutions of 8.7, 17.5, and 35% HP were applied to the discolored resin brackets for 15 min. Resin brackets were then stored in distilled water for a week by repeating this whitening process thrice. The whitening efficacy was evaluated according to ISO 28399:2011. The SBS was measured using a universal testing machine. The microhardness and microstructure of the resin brackets were observed using a microhardness tester and field-emission scanning electron microscopy (FE-SEM). All the results were analyzed using a one-way analysis of variance analysis and Tukey’s post-hoc test (p=0.05). Results. All the experimental groups demonstrated a significant whitening effect on the discolored resin brackets compared to the control group (p<0.05). In particular, 35% HP showed faster color changes than the other groups (p<0.05). The microhardness of the resin bracket was lower in 35% HP than in the control group (p<0.05). FE-SEM analysis revealed no significant difference between groups. Conclusions. HP application at > 8.7% and < 17.5% concentrations whitens discolored resin brackets while not deteriorating the SBS, surface hardness, and microstructure. Clinical relevance. Dental clinicians can safely use HP within the recommended range to achieve effective aesthetic outcomes without compromising bracket performance and durability.
... Over-the-counter ürünlerle yapılan beyazlatma; hekim gözetiminde olmadığında kontrolsüz uygulanma riskini barındırır. 4 Mikroabrazyon yöntemi, invaziv bir teknik olduğu için nadiren tercih edilir. 5 Ofis tipi diş beyazlatma yöntemi; sıklıkla %30-35'lik hidrojen peroksit (HP) içeren bir ajanın klinik ortamında dişlere uygulanmasını kapsar. ...
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Bu olgu alt ve üst keser, kanin ve premolar dişlerin tek seansta %35 hidrojen peroksit içeren jel ile beyazlatılmasını içermektedir. 29 yaşındaki erkek hasta, dişlerinin renginden memnun olmaması şikayetiyle kliniğimize başvurdu. Gün ışığında yapılan muayenede hastanın diş renginin VITA classical A1 - D4 skalasına göre C2 olduğu tespit edildi. Estetik bölgedeki dişler olan alt ve üst keserler, kaninler ve premolar dişler beyazlatmaya dahil edildi. %35 hidrojen peroksit içeren jel (BlanQuest Pro) 35 dakika boyunca uygulandı. Gün ışığında yapılan değerlendirmede beyazlatma sonrası diş renginin VITA classical A1 - D4 skalasına göre A1 olduğu gözlendi. Hassasiyet oluşumunu minimize etmek amacıyla dişlere hassasiyet giderici ajan uygulandı. Hastaya postoperatif bilgilendirme yapıldı. Tedavi sonunda yüksek hasta memnuniyeti ve tedavi başarısı elde edildi. Sonuç olarak başarılı bir tedavi için uygun materyal/ tedavi yöntemi tercihi, vakanın gerektirdiği şartlar göz önünde bulundurarak yapılmalıdır.
... These products' lack of data and easy availability is concerning, as it may potentially harm the customers' dentition. Because of their 'Do-It-Yourself' nature, over-the-counter products also pose the risk of mishandling, overuse, and abuse [18]. ...
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This in vitro study investigated the extrinsic tooth-whitening effect of bleaching products containing polyphosphates on the dental enamel surface compared to 10% carbamide peroxide (CP). Eighty human molars were randomly allocated into four whitening-products groups. Group A (control) was treated with 10% CP (Opalescence). The other groups with non-CP over-the-counter (OTC) products were group B = polyphosphates (iWhiteWhitening-Kit); group C = polyphos-phates+fluoride (iWhite-toothpaste); and group D = sodium bicarbonate (24K-Whitening-Pen). L *, a *, b * color-parameters were spectrophotometer-recorded at baseline (T0), one day (T1), and one month (T2) post-treatment. Changes in teeth color (ΔEab) were calculated. Data were analyzed using ANOVA and the Bonferroni test (α = 0.05). Groups A, B, and D showed significant differences in ΔL*&Δa
... The lack of data and ease of access to these products is concerning, as they may harm customers' dentition. Over-the-counter products are vulnerable to mishandling, overuse, and abuse due to their 'do-it-yourself' nature [8]. Citric acid is considered as one of the natural products for tooth whitening and many of the tooth-whitening products contain citric acid in low concentrations to avoid enamel erosion [9,10]. ...
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Background: To evaluate the efficacy of new over-the-counter tooth-whitening products on enamel surface roughness and microhardness. Methods: A total of 120 enamel specimens were prepared and randomly allocated into six groups. Group A was treated with 10% carbamide peroxide; Group B was immersed in distilled water; Group C was treated with hydrated silica, sodium hexametaphosphate toothpaste; Group D was treated with sodium bicarbonate; Group E was treated with 0.25% citric acid; and Group F was treated with hydrated silica, charcoal powder. Results: A, B, and D demonstrated decreased Ra, whereas Groups C, E, and F showed an increased Ra after whitening. The changes in Ra from T0 to T1 in each group was statistically significant (p < 0.001) except for Group B (p = 0.85). The groups showed decreased KHN after whitening, except for specimens in Group B (distilled water). The KHN from T0 to T1 decreased significantly for groups A, C, E, and F (p = 0.001). Significant difference was observed at T1 (p < 0.0001). Conclusion: Within the limitations of this study, it could be demonstrated that surface roughness and enamel microhardness changes were influenced by the type, composition, and exposure time of the whitening product.
Few dental treatments have been more successful and conservative in nature than tooth whitening. Therefore, it is noteworthy to reflect on the efforts of pioneers in our dental profession that continuously attempted to search for the most effective and safest whitening agent. This quest has extended to determine the best whitening technique to meet our patients’ desires and expectations about the esthetic outcome. Here, a short history of tooth whitening agents developed and employed based on the type of discoloration is summarized, as is our current knowledge on the relative efficacy and safety of various types of tooth whitening regimens available. The information on proper diagnosis and treatment planning will guide the clinician in establishing a step-by-step protocol for determining the etiology of the discoloration, selecting the best whitening technique, and monitoring tooth color until the desired outcome has been achieved.
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Background: An increasing number of patients are using natural homemade remedies such as strawberries, banana peels, coconut oil rinse, basil, lemon, activated charcoal, apple cider vinegar, baking soda, and turmeric to obtain whiter teeth. However, studies on these natural whitening products are limited. Aim: To evaluate the effectiveness of different homemade tooth-whitening agents in vitro. Materials and methods: Ninety caries-free extracted anterior and premolar teeth were collected, cleaned, and sectioned at the roots. The teeth were mounted in epoxy resin (buccal surface) and stored in 0.2 % thymol solution, and were treated with one of the following six whitening agents: baking soda, activated charcoal, lemon juice, strawberries, Colgate Optic Whitening toothpaste, and Opalescence 20 % home-bleaching system. The enamel shade in each sample was measured four times using a spectrophotometer. Baseline measurements for ΔE and (L*, a*, b*) were obtained, and the second measurement was obtained after 5 days. The third reading was obtained on the 10th day, and the fourth reading was obtained at the 4th week to measure colour stability. One-way analysis of variance and post-hoc Tukey tests were used for statistical analysis. Results: ΔE measurements showed a significant difference on the 10th day in all groups except the lemon group (P = 0.164), while all groups showed a statistically significant difference at the 4th week. The mean colour change differed remarkably between the first and fourth readings. The highest change was observed in the lemon group (44.0 ± 2.9), closely followed by the Opalescence 20 % and Colgate Optic Whitening toothpaste groups. The lowest change was observed with strawberries (38.2 ± 4.8). ΔE showed a significant difference in all groups except the turmeric group. Conclusion: Statistically significant differences were obtained with baking soda, activated charcoal, strawberries, lemon juice, Colgate Optic Whitening toothpaste, and Opalescence 20%. Further studies are required to evaluate the effects of these agents on surface roughness and colour stability.
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Objetive: To compare in vitro bacterial adherence on teeth submitted to whitening with 50% ethanolic extract of Musa paradisiaca and 35% hydrogen peroxide. Material and Methods: The study was experimental and used 18 premolars that were grouped into: G1 (control), G2 (50% ethanol extract of Musa paradisiaca) and G3 (35% hydrogen peroxide). The teeth were then exposed to a Streptococcus mutans culture for 24 hours, followed by centrifugation in thioglycolate broth. A culture on trypticase soy agar was done with a 1 in 100 dilution, and after 48 hours colony forming units (CFU) were counted. Statistical analysis was performed using the ANOVA test, complemented by the Bonferroni post-hoc. Results: Bacterial adherence was 77x105 CFU/ml in Group 3 using 35% hydrogen peroxide, 40x105 CFU/ml in Group 2 using 50% ethanol extract of Musa paradisiaca, and 89x104 CFU/ml in Group 1 (control). The difference between the three groups was significant (p=0.000). Conclusion: Both whitening methods cause bacterial adherence to the tooth surface, although to a lower degree with Musa paradisiaca.eses.
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The objective of this study was to evaluate the effect of natural bleaching products on the color, whiteness, and superficial properties of dental enamel. Seventy fragments of bovine teeth were obtained (6mm x 6mm x 2mm). Initial surface roughness (Surfcorder SE1700, Kosakalab), microhardness (HMV-2, Shimadzu), color (EasyShade, VITA), and surface gloss (Micro-Gloss 45º BYK, Gardner) readings were done. Samples were separated into five groups (n=14) according to the treatments used: CT-conventional toothpaste (negative control); CH-charcoal; TU-turmeric; BP-banana peel, and CP16%-16% carbamide peroxide gel (positive control, 4 h/day for 14 days), and then brushed for 560 cycles (T1) and 1200 cycles (T2), equivalent to 14 and 30 days of brushing. New measurements were performed after T1 and T2. The whiteness index for dentistry change (∆WID) and Weight loss (Wl) were calculated. CP16% demonstrated the highest (p<.05) color change (ΔE00) and ∆WID (2-way ANOVA, Bonferroni, p<.05). Surface gloss alterations were lower for TU, CP16%, and BP. CT and CH increased surface roughness (p<.05). CP16% decreased enamel microhardness. CH presented medium abrasiveness, and CT and TU, low abrasiveness. The popular bleaching products were not efficient for tooth whitening. Furthermore, brushing with charcoal increased the enamel surface roughness, and CP16% decreased enamel microhardness over time.
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Objectives: To examine different types of restorative materials used in children as well as primary and permanent teeth enamel when affected by erosive foods. Materials and method: Buttermilk, fruit yoghurt, Coca-cola, fruit juice, Filtek Z-250, Dyract Extra, Fuji II LC, and Fuji IX and tooth enamel were used. Measurements were performed on 1-day, 1-week, 1-month, 3-month, 6-month time periods by using ATR-FTIR technique and surface of the specimens were examined with SEM. Results: Permanent tooth showed the least change among human tooth samples when compared to restorative materials. Among filler materials, the most change was observed in Fuji IX. In terms of beverages the most changes on absorption peaks obtained from spectra were seen on the samples held in Coca-Cola and orange-juice. Conclusion: The exposure of human enamel and restorative materials to acidic drinks may accelerate the degradation process and so reduce the life time of filler materials at equivalent integral exposure times longer than three months. Clinical Relevance Erosive foods and drinks having acidic potential destroy not only tooth enamel but also restorative materials.
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To measure, in vitro, the pH and titratable acidity (TA) of various soft drinks and to assess the erosive effect of smoothies using an in situ model. The in vitro phase of this study included measuring the inherent pH of six different commercially available smoothies, diet coke, and citric acid 0.3% (positive control) using a pH meter. The TA was determined by titration with NaOH. In the second part of the study, an in situ model was used. An upper removable appliance capable of retaining two enamel slabs was constructed and worn by 14 volunteers. The drinks under test were Innocent(®) strawberries and banana smoothie and citric acid. Volunteers were instructed to dip the appliance in the test solutions extra-orally five times daily for 2 min each time for 21 days. Measurements of enamel loss were made by surface profilometry and microhardness. Diet Coke was found to be the most acidic drink (pH 2.61), whereas Innocent(®) mangoes and passion fruit smoothie showed to be the least (pH 3.9). With regard to TA, Innocent(®) blackberries, strawberries, and blackcurrant smoothie had the highest TA requiring 10.8 mol of NaOH to reach pH 7.0, whereas citric acid required only 3.1 mol of NaOH to reach the same pH value. Surface profilometry and microhardness testing revealed that citric acid caused a statistically significantly greater tooth surface loss compared with smoothie after 21-day pH cycling protocol. Smoothies are acidic and have high TA levels. Innocent(®) strawberries and banana smoothie had an erosive potential to the teeth. However, its erosive effect was significantly less compared with citric acid after 21-day pH cycling protocol using an in situ model.
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Introduction: Recent health promotion campaigns have encouraged the public to consume at least five portions of fruit and vegetables per day. Many see consuming fruit smoothies as a way of achieving this. Objective: To ascertain the potential or otherwise for fruit smoothies to bring about dental erosion. Design: Laboratory study.Method This was an in vitro investigation in which five varieties of shop bought fruit smoothies, including a 'thickie' were investigated, with respect to their initial pH, titratable acidity and effect upon exposure to the surface microhardness and profile of extracted human teeth. In addition their performance was compared to negative (Volvic(™) water) and positive (orange juice) control drinks as well as a homemade smoothie, based upon the recipe of one of the commercially bought drinks, from which ingredient omissions were made. Results: The majority of the drinks investigated had a baseline pH below the critical pH of enamel (5.5) and required comparable volumes of 0.1M NaOH to raise their pH to neutrality as the positive control. Only two drinks (Volvic(™) still mineral water, the negative control, and the yoghurt, vanilla bean and honey 'thickie') displayed a higher pH, though to neutralise the thickie, a lesser quantity of alkali addition was required. The immersion of the tooth samples in the drinks brought about reductions in their surface hardness (expressed as a percentage change of median hardness) but these were only significant (p <0.001) for the cranberry, blueberry and cherry fruit smoothie and homemade strawberry and banana fruit smoothie. There was no reduction in surface hardness in the case of the teeth immersed in the thickie. Omission of certain ingredients from the homemade smoothie affected the magnitude of surface hardness reductions seen. With regard to the loss of surface contour of the tooth samples following immersion in the drinks, as assessed by depth loss, there were significant differences between the drinks (p = 0.0064) with the thickie and negative control not causing depth loss and the kiwi, apple and lime smoothie producing most depth loss (28.26 (5.45) μm). Conclusions: Within the limitations of this study some fruit smoothies have the potential to bring about dental erosion if consumed irresponsibly. This can be influenced by ingredient variations. In order to minimise the risk of developing dental erosion, without removing the claimed nutritional benefits of their consumption, their consumption should be confined to mealtimes.
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To review current status of hand held systems for tooth color matching in vivo and corresponding research. "Medline" database from 1981 to 2010 were searched electronically with key words tooth, teeth, color and dentistry. Spectrophotometers, colorimeters and imaging systems are useful and relevant tools for tooth color measurement and analysis, and for quality control of color reproduction. Different measurement devices either measure the complete tooth surface providing a "color map" or an "average" color of the limited area [3-5mm] on the tooth surface. These instruments are useful tools in color analysis for direct or indirect restorations, communication for indirect restorations, reproduction and verification of shade. Whenever possible, both instrumental and visual color matching method should be used, as they complement each other and can lead towards predictable esthetic outcome.
For most of the past decade, it has been tough to find growth in consumer sectors such as packaged goods, media, food, and electronics. The proliferation of new brands and products has made operations more complex and expensive, while consolidation among retailers and the rise in private-label store brands has shifted pricing power away from suppliers in household and packaged goods. A few consumer companies, however, are prospering or starting down new avenues to growth. These firms have moved beyond product innovation to emphasize demand innovation, which entails understanding the higher-order needs of consumers, and then creating service and product solutions that directly address those needs. Mercer’s research has documented at least a dozen patterns of demand innovation in consumer markets. Some are relatively simple steps to enhance a product or service and thereby steal market share and expand margins. Others allow companies to leverage their assets in more radical ways, opening up entirely new opportunities. The experiences of Kraft, Procter & Gamble, and Netflix show how consumer companies can improve the consumer experience and find incremental ways to grow in the process.
This clinical study compared the efficacy of three different bleaching techniques with respect to the bleaching times required in order to achieve six grades of whitening in human teeth. Any side effects that were noted and the patients' acceptance of the method were recorded by a visual analog scale ranging from 0 to 10. Moreover, epoxy casts from the study teeth were analyzed by scanning electron microscopy in order to detect any potential changes in the enamel surface due to treatments. Thirty-nine volunteers participated in the study and were allocated randomly to one of three different bleaching treatments: Group A (n=13) used Whitestrips (over-the-counter technique; one cycle=30 minutes), Group B (n=13) used Opalescence PF 10% (at-home bleaching technique; one cycle=8 hours) and Group C (n=13) used Opalescence Xtra Boost (in-office bleaching technique; one cycle=15 minutes) until a defined whitening of six tabs compared to the baseline were reached (assessed by the VITA shade guide). All three methods achieved six grades of whitening. The mean treatment time required to reach the defined level of whitening was 31.85 +/- 6.63 cycles in Group A, 7.15 +/- 1.86 cycles in Group B and 3.15 +/- 0.55 cycles in Group C. All products differed significantly from each other in terms of treatment cycles and required treatment time (p < 0.001 by ANOVA and Mann-Whitney-U-test). Using the VA scale, side effects noted within the three groups were minimal. Tooth hypersensitivity ranged from 2.62 (Whitestrips) to 3.38 (Opalescence PF), and gingival irritation ranged between 0.23 (Opalescence Xtra Boost) and 0.85 (Whitestrips). The most accepted method was the at-home bleaching technique. None of the teeth studied showed detectable enamel surface changes in the subsequent SEM analysis using 200x and 2000x magnification.
Objectives: This randomized, parallel group, single centre clinical trial was conducted to evaluate the safety and compare the whitening efficacy for an extended wear of an experimental 9.5% H₂O₂ high-adhesion whitening strip, relative to a marketed 10% H₂O₂ control strip. Methods: Twenty-nine eligible adult volunteers were randomly assigned to either a treatment series with an experimental 9.5% H₂O₂ high-adhesion whitening strip at home for 2h, once a day, for 8 days; or a marketed 10% H₂O₂ whitening strip for 30 min, on a similar daily regimen. Tooth color/whitening progression was recorded under standardized lighting conditions at baseline, day 3, day 5, and day 9, via digital imaging. Outcomes were reported using the CIELAB system. Usage safety was also assessed at each follow-up visit. Whitening efficacy for each group was investigated using a paired-difference t-test. The treatment groups were compared among each other using the analysis of covariance, with the baseline value and age as the covariates. Results: Both treatment groups demonstrated statistically significant mean color improvement from baseline for b* (yellow ness) and L* (lightness) at each post-baseline visit. In addition, the 2-h high-adhesion strips demonstrated significantly greater improvement in b* and L* relative to the 30-min strip group at each follow-up visit. Conclusions: The 2-h regimen for the 9.5% H₂O₂ high-adhesion whitening strip was more efficient for tooth whitening than the 30-min regimen of 10% H₂O₂ whitening strip. Both treatments were well tolerated and the use of the test products during the study time frame was considered safe. Clinical relevance: Extending the daily wear time of whitening strips can improve the efficacy of the treatment and ultimately shorten the length of the treatment without any significant adverse effects.
Objective: To investigate how enamel loss due to erosion, and due to cycling of erosion and abrasion, depends on compositional parameters of soft drinks, and particularly whether the thickness of the erosive softened layer is a function of drink composition. Setting: University dental hospital research laboratory in the UK, 2004. Materials and methods: Six drinks were chosen based on their popularity and composition: apple juice, orange juice, apple drink, orange drink, cranberry drink and 'ToothKind' blackcurrant drink. Group A samples (n = 36) were exposed to soft drinks at 36 degrees C for six consecutive 10 minute periods. Group B samples (n = 36) were subjected to alternating erosion and toothbrushing, repeated six times. Enamel loss was measured using optical profilometry. Results: Group A: significant enamel loss was seen for all drinks (p < 0.001). Erosion was correlated with pH and calcium concentration but not phosphate concentration or titratable acidity. Group B: significant additional material loss due to toothbrush abrasion occurred with all drinks. Abrasive enamel loss differed between the drinks and was positively correlated with drink erosive potential. Conclusion: Enamel loss by erosion is exacerbated by subsequent abrasion. The amount of softened enamel removed by toothbrushing is a function of the chemical composition of the erosive medium.
Objective: To evaluate clinical effectiveness, color rebound and sensitivity of 22% carbamide peroxide (CP) with 3% potassium nitrate. Methods: Twenty-one participants were enrolled and treated overnight for 2 weeks with 22% CP (Venus White, Heraeus Kulzer). Visual color measurement was performed and expressed in shade guide units (SGU) of Vita Classical (VC) and Vita Bleachedguide 3D Master (BG) shade guides. Instrumental color measurements were performed using an intraoral spectrophotometer (Vita Easyshade Compact, EC). Color measurements were taken on a canine and central incisor at baseline, 2, 3, and 4 weeks. Participants documented sensitivity and data were analysed with Wilcoxon and Bonferroni correction at the 0.05 level of significance. Results: Mean BG SGU difference immediately, 1 and 2 weeks postbleaching compared to baseline was 4.9 (2.1), 4.5 (2.2) and 4.6 (2.0), respectively. Corresponding VC values were 7.0 (3.5), 6.4 (3.3) and 6.5 (3.4), while corresponding ΔE* values were 8.3 (4.1), 8.1 (4.0) and 7.9 (3.5). For visual shade evaluation there was a significant decrease in SGU from baseline and each subsequent week, p<0.001. There was no difference between week 3 and week 4 using VC or BG. For instrumental color measurements, there was no difference from week 2 to week 3 for canines and generally no difference between week 3 and week 4 for incisors. Conclusions: Visual and instrumental evaluation showed rebound occurred 1 week postbleaching with 22% carbamide peroxide and 3% potassium nitrate. In general, color was stable at 2 weeks postbleaching. Participants reported low sensitivity levels with a mean value of below 2 on a 0-10 scale. Clinical significance: This study demonstrates efficacy with overnight usage of 22% carbamide peroxide with 3% potassium nitrate and demonstrates postbleaching color is stable at two weeks with low tooth sensitivity.
This study evaluated the time necessary for at-home whitening (HW) to match the results of an in-office (OW) treatment, side effects and patients' preferences/perceptions. The tooth color change of 20 subjects was measured using a shade guide (BSG) and spectrophotometer (ES). Color difference was calculated: delta E* = [(delta L*)2 + (delta a*ab)2 + (delta b*ab)2]1/2. The whitening treatments were randomly applied to the right or left maxillary anterior teeth, in-office, with 25% hydrogen peroxide or at-home, overnight, with 10% carbamide peroxide. The tooth color was evaluated at baseline, one day after OW, six days (five days after HW) and at 20 days (14 days after HW and 19 days OW). Subjects rated their tooth and soft tissue sensitivity (1-10 scale). The results were analyzed by two-way RM ANOVA/Tukey's and Mann-Whitney (p<0.05). At six days, the teeth that were treated with HW and OW presented delta E* = 5.2 and 6.6, respectively, delta BSG = 3, and at 20 days, they presented delta E* = 6.2 and 6.6, respectively, delta BSG = 3. Less than 40% of the subjects experienced tooth sensitivity after OW and HW. No subjects experienced tooth and gingival sensitivity at 20 days. Seventy-four percent preferred HW over OW, 63% recommended OW and 100% recommended HW. While there was a subtle difference in delta E* between HW and OW at six days, the measurement of delta E* and delta BSG agreed that five days of home whitening produced the same results as a single in-office treatment. The tissue and teeth sensitivity were mild and transient. Subjects preferred and would recommend HW over OW.